Top PDF Challenges in topside ionospheric modelling over South Africa

Challenges in topside ionospheric modelling over South Africa

Challenges in topside ionospheric modelling over South Africa

Due to the properties of high frequency (HF) radio wave reflections the topside ionosphere can not be probed by ground-based ionosondes, which are limited to sounding the bottomside ionosphere. Any radio signal that has a frequency greater than the critical frequency passes beyond the peak height of the F2-region and is not reflected, and thus provides no information. The advent of satellite mounted ionosondes (topside sounders) in the 1960s added a new dimension to the study of the ionosphere. Topside sounders perform measurements of the topside ionosphere comparable to the measurements of the bottomside ionosphere performed by the ground-based ionosondes. Other techniques that permit the measurement of the region above the level of the F2-layer peak include the use of rockets and Incoherent Scatter Radars (ISR) systems. Instruments can be mounted on rockets to make direct measurements of the ionospheric parameters, such as relative concentration of the various ion species and electron/ion temperatures. However, such measurements are brief and can only be made along the trajectory of the rocket. Ionospheric observations using rockets represent “direct” methods where the assumptions and approximations that must be made involve only local parameters, and therefore only localised measurements are recorded that can lead to localised conclusions. Incoherent Scatter Radars provide another method for determining electron density distribution in the topside ionosphere. In this method, energy is propagated into the ionosphere from an extremely powerful pulsed radar. Some of the echos received are due to the scattering of waves from the individual electrons in the ionosphere. The power of the returned signal is directly proportional to the electron density.
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Challenges in Managing Diffusion of Telemedicine Technology in South Africa

Challenges in Managing Diffusion of Telemedicine Technology in South Africa

3.2. Health Technology Infrastructure Investments Strategic planning and management of technological in- vestments in health care systems, hospitals and clinics are the most difficult challenges facing health policy makers and planners in South Africa. Although the public health care system is far from being homogenous, it is evident that two large groups of technologies are considered simultaneously - namely, technology for primary health care services and hospital-based technologies for curative services. The effec- tive management of the two groups of technologies will lead to competitive delivery of health care services – higher outputs at lower costs and better access to health care ser- vices. It is therefore imperative that investments in health technology infrastructure should take into account techno- logical relationships between various levels of health care delivery services to ensure the cost-effective utilization of technological investments and better return on investment. 3.3. Telemedicine Technology Diffusion Management
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Challenges faced by unaccompanied minor-refugees in South Africa

Challenges faced by unaccompanied minor-refugees in South Africa

Unaccompanied minors and refugee children from Africa had specifically fled from their war-torn countries to South Africa with hopeful aspirations of sharing the dream of democracy and human rights. Hillier (2007) asserts that the challenges faced by these children on their journeys out of their countries of origin include exploitation (sexual and non-sexual) by truck drivers, border officials and police officers, who are initially viewed as their protectors. Fritsch et al. (2009) concur and refer to accounts by refugees and children who reported that their maltreatment and exploitation by officials and police officers often began at the border posts. Van der Burg (2005:8) also highlights the point that unaccompanied minors also experience the following difficulties upon their arrival in South Africa: language barriers, insecurity, inadequate housing and problems with integration into schools as they are perceived to be “different” from the local population. They might also be denied access to social services and legal documentation.
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Financial challenges faced by SMMEs in Gauteng South Africa

Financial challenges faced by SMMEs in Gauteng South Africa

Despite the country’s economic growth in recent years, the unemployment rate has not fallen substantially. By the second quarter of 2014, the official unemployment rate of South Africa was estimated to be 25.5% (Statistics SA, 2014). SMMEs contribute to socio-economic development of a nation by creating employment and thus can play a vital role in achieving the vision 2030 of the National Development Plan (NDP) to reduce the employment to 6% through the creation of about 90% jobs in small and expanding firms (NPC, 2011). The current trend in South Africa is that credit is being tightened everywhere as banks tend to take precautionary measures against financial transactions. Businesses therefore find it very hard to survive. This results in increased layoffs and closures which affect the anticipated growth rate considerably. In an attempt to dampen these challenges the National government has introduced a favourable tax regulation for this sector which is still viewed as the country’s solution to the unemployment rate. Through these measures the National government intends to particularly encourage youth, women and people with disabilities to start and sustain their own businesses.
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Challenges in Mortgage Lending for the Under Served in South Africa

Challenges in Mortgage Lending for the Under Served in South Africa

We pointed out earlier that governance and other non-commercial reasons which inhibit housing finance needed attention. Although for South Africa as a whole, less than 5% of subsidised houses are credit linked, evidence from the case study area shows that government guarantees helped in attracting the private sector funding for many house purchasers. Thus, given that many potential borrowers have inadequate incomes to fulfil the down payment (deposit) requirement, it would be a worthwhile effort for government and/or employers to develop guarantees for such households. But such programmes should separate beneficiary groups facing different challenges in accessing finance and develop different interventions for each. This should be guided by principles of efficiency. That is, it should aim at achieving lowest cost per beneficiary and maximise beneficiary contribution to avoid replacing the expenditures recipient would make anyway. Such initiatives could encourage beneficiaries to contribute from own sources by for example, making own savings a criterion to qualify for a subsidy.
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Challenges in Implementing HIV Load Testing in South Africa

Challenges in Implementing HIV Load Testing in South Africa

The South African antiretroviral treatment guidelines recommend the use of human immunodeficiency virus type 1 (HIV-1) load testing for patient monitoring and, in particular, to assist in switching to second-line treatment regimens. There are significant challenges to implementing HIV load testing on the scale that is required in South Africa. To put this in context, ∼ 560,000 HIV-infected individuals are receiving antiretroviral therapy, and program recommendations include viral load testing twice per year. Currently, a 3-tiered labo- ratory infrastructure exists with tertiary facilities and, to some extent, secondary laboratories able to implement quantitative HIV nucleic acid testing. Challenges include high sample volumes, transportation logistics from remote sites, costs, phlebotomy in children, a national skills shortage, and sample throughput of technology platforms. Several approaches are thus being explored simultaneously: (1) the feasibility of establishing higher throughput and more automated central laboratories; (2) improvement of current sample collection, trans- portation, and storage techniques; (3) alternative viral load technologies, including flow-based marker screening approaches to reduce testing volumes, and (4) point-of-care viral load testing strategies for clinics. The de- velopment of appropriate solutions for each laboratory tier in South Africa will require close collaboration between researchers in the field and partners in industry.
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Investigating challenges faced by refugees in Port Elizabeth, South Africa

Investigating challenges faced by refugees in Port Elizabeth, South Africa

In 2012 South Africa received 82,000 applications by asylum seekers. Notably, this accounted for one tenth of the applications worldwide (UNCHR, 2012:8). South Africa has officially only accepted refugees since 1993, when it co- signed the Basic Agreement with the UNCHR to deal with the issue of Mozambican refugees. Prior to this period, refugees were not allowed into the country due to the restrictive policies of the Apartheid government (Handmaker, 2001; Handmaker, de la Hunt and Klaaren 2008). In 2000 the Refugee Act 130 of 1998 came into force. Therefore, South Africa’s social and legal infrastructure is relatively unfamiliar with receiving refugees (Handmaker et al., 2008:1). According to the Refugee Act 130 of 1998 and the South African Constitution, refugees have largely the same rights as South African citizens. However, refugees and other migrants have been reported to face various challenges in South Africa, including access to basic services and xenophobia (Reference). The study will hence aim to describe the experience of refugees in South Africa in light of their needs and rights.
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Challenges Confronting Nigeria-South Africa Relations.

Challenges Confronting Nigeria-South Africa Relations.

government, military or civilian inevitably became a shade moderation, militancy or radicalism of the first one (Bukar, B. 2000). This article examines the challenges constraining Nigeria’s Afrocentric efforts with emphasis on South Africa whose issue was one of the most constant concerns of the Nigerian government since the attainment of independence. At the first debate in the House of Representatives in November 1960, the Prime Minister Abubakar Tafawa Balewa in apparent reference to South Africa reassured the leader of the opposition that on the issue of South Africa, “Nigeria has a duty to see that there is equality of treatment to all mankind”. Concerning overt demonstration of commitment, (under cooperation) the 1960 saw Prime Minister Tafawa Balewa in the frontline of diplomatic battles (in the OAU and Commonwealth councils) against Pretoria’s Apartheid system of government. Balewa, in his speech to the United Nations General Assembly, outlined the contours of Nigeria’s foreign policy and her position that apartheid was unacceptable to the Nigerian people. And in a relatively more aggressive stance, the prime minister further addressed the House of Representatives Prime Minister’s meeting in London in March 1961.
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Discourses and practices in institutionalised nursing in South Africa : challenges for care

Discourses and practices in institutionalised nursing in South Africa : challenges for care

production to address the challenges of the primary healthcare sector where nurses are such central role players. There are clearly resource challenges in South Africa which may undermine caring practices; however, this article also foregrounds the dominant discourses that shape international and local nursing, and which arguably mitigate against care that is democratic, socially responsive and sensitive to the diverse care needs of communities and individuals. Drawing on Tronto’s political ethics of care and on Foucaultian frameworks, the paper analyses the processes currently shaping the experience of nurses and practices of care. Key themes are the hierarchical, regulatory framework of surveillance in nursing, the dominance of biomedical discourse and the mechanistic framework which fragments nursing practice. These aspects not only disempower nurses and deny them recognition but, together with institutional disregard for the need for self-care, also reproduce a system which is inherently unable to provide humane healthcare.
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Challenges of the Migration and Integration of Ethiopian Entrepreneurs to South Africa

Challenges of the Migration and Integration of Ethiopian Entrepreneurs to South Africa

Bribery, corruption and hostility at the remaining RRO compounds the difficulties faced by asylum seekers in ensuring that their permits do not expire. Furthermore, research conducted by ACMS and others shows that status determination interviews are very often flawed. For instance in one year over 90% of applications lodged at the Musina RRO were rejected. According to a study conducted by Amnesty International, the rejection rate for all refugee applications in the country currently stands at an appalling 96% (Tolmay, 2018). Applicants are therefore suddenly told to leave the country even if they have been living and working here for numbers of years. This has created a huge backlog in the appeal system, which the Refugee Appeals Board is unable to address.
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Challenges to the sub judice rule in South Africa

Challenges to the sub judice rule in South Africa

accused has a constitutional right to a fair trial and that his or her reasonable perception in this regard, it is submitted, is crucial. I also agree with the present Chief Justice of Canada that this right may never be compromised. On the other hand, the value of freedom of expression as a fundamental right has overwhelmed countries where democratic values are held dear: especially where they have suffered under totalitarian regimes. Furthermore, judges, as a result of their experience and expertise, ignore what the press and broadcasters say. They only consider the facts before them. There is also a tendency, within some democracies, to soften the effect of the sub judice rule. One experiences that from the Canadian judgement in Dagenais, the South African judgement in Midi and the approach of the European Court of Human Rights, as discussed above: and also, of course, from the approach of the United States courts. Proposals in Australia also tend towards more freedom and England has also adopted a reality test.
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Diverse challenges for coloured women entrepreneurs in South Africa

Diverse challenges for coloured women entrepreneurs in South Africa

Socio-economic links financial and social issues together. Adhikari (2004:171-173) claims that the coloured community is highly sensitive to issues of race. This sensitivity emanates, firstly, from the marginality which has made them vulnerable in a society in which race remains the primary form of social identification and therefore of social and political solidarity. The skilled and well-educated coloured middle classes have profited from the extension of civil liberties, and many have been able to take advantage of opportunities that became available to formerly disadvantaged people through affirmative action and black economic empowerment. Initiatives, the working class Coloured, have been victims of jobless economic growth and increasing desire amongst employers in the formal sector to hire Africans in order to have a more racially representative work force. All over the world there is a realization that the best way to tackle poverty and enable the community is to improve its quality of life through social mobilization of poor, especially women into self-help groups (Bharthvajan, 2014). According to Aidis et al., (2007:157) in a variety of countries, the perception is that entrepreneurship is an appropriate career choice for men and not for women, only for the poor and not for the educated, which in most cases are women. However, Church et al., (2008:102-116) argues that the safety and the protection of women entrepreneurs in the informal economy are complex because there are numerous stories of killings, harassment and rape of female vendors and micro business owners. This results in stress, constant fear and not having the opportunity to freely choose their business location.
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No. 20: Migration of Skills in South Africa: Patterns, Trends and Challenges

No. 20: Migration of Skills in South Africa: Patterns, Trends and Challenges

9.11 The call for developed nations to assist in capacity-building and the development of African countries was repeatedly made during the 2005 Regional Hearings for Africa of the Global Commission on International Migration. There is a sense that those who have for years been taking from the African continent should now be putting something back in. The question of where development aid could best be deployed was answered by the need for investment in Africa’s universities. It makes sense in South Africa that if skilled professionals are being lost, more skilled professionals should be developed. Universities that lose academics to overseas postings often need to pay more to secure a foreign academic to fill the vacant position. Ironically, they are willing to pay more for a foreigner when investing the same amount in a national could have prevented the loss in the first place.
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Challenges and prospects for small-scale mining entrepreneurs in South Africa

Challenges and prospects for small-scale mining entrepreneurs in South Africa

Many would agree that small-scale mining initiatives are the cornerstone of the rural economy in terms of job creation and the eradication of poverty. However, small-scale mining is still poverty-driven rather than entrepreneurially driven. Childs (2014:1), citing the International Labour Organization (1999), makes the point that more than 12 million people are either directly or indirectly employed by small-scale mining in Southern Africa alone. A similar view is presented by Hilson (2012:1663-1674). Small-scale mining entrepreneurs in Southern Africa employ whoever is available in the local community, thereby making it the leading employer in Southern African rural communities (Hilson, 2012:1663-1674). Yakovleva (2007:30) notes, however, that small-scale mining entrepreneurs predominately create jobs for uneducated women. This helps to eradicate poverty, rather than to grow their businesses. It seems that Yakovleva (2007:30) and Hilson (2012:1663-1674) are right when they argue that although small-scale mining is the leading employment provider in rural communities throughout multiple countries, it is not an entrepreneurially driven business. As in other countries, South African small-scale entrepreneurs cannot establish sustainable enterprises in the parts of the country in which they work and thus cannot exploit the prospects the mining sector offers.
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Challenges of instructional leadership in historically disadvantaged schools in South Africa

Challenges of instructional leadership in historically disadvantaged schools in South Africa

The research sub-question that is under consideration in this section “Do principals know what is expected of them in terms of the expectations of the Department of Education‟s policy documents of curriculum policies? Phrased slightly differently, the question is to what extent are school principals conversant with the Department of Education (DoE) expectations of them with respect to their knowledge of general policy documents and curriculum policies in the changing school climate, as well as how principals view their role in the development and the implementation of new curricula. In relation to this question, participants, i.e. principals, expressed that they were in the “forefront of change and curriculum implementation” in their schools, and expressed an understanding that they needed more development in this area as part of their professional development strategy in order to be better equipped to deal with challenges during implementation. The situation described by these principals resonates with the views espoused by researchers such as Blasé & Blasé (2004) who have maintained that principals need to possess a wide array of competencies (in this case an understanding of the curriculum and its implementation) in order to lead their schools effectively because they are directly in charge of policy implementation at school level.
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Human capital formation: History, expectations, and challenges in South Africa

Human capital formation: History, expectations, and challenges in South Africa

Recent empirical work shows significant effects of LER and class size on learner achievement, although the literature as a whole contains some ambiguity (Hanushek 1998). The difficulty in identifying causality arises from potential endogeneity in the number of learners and unobserved fixed com- ponents specific to school and community, which is likely to be correlated with school inputs. 1 For example, Lazear (2001) argues that the effect of LER on learner achievement could be empirically ambiguous because of (often unobserved) heterogeneity in learner quality, that is, discipline. In his model, the optimal size of a class (LER) increases if learner discipline improves, since the probability of disruption in a classroom decreases. To avoid such a correlation between LER and unobservables, recent studies use exogenous variations (changes) in LER and class size to identify the effect on learner achievement (for example, Angrist and Lavy 1999; Case and Deaton 1999; Krueger 1999; Hoxby 2000). In these studies with exogenous variations in LER, the effect is found to be significant. In the context of South Africa, Case and Deaton (1999) show that among Africans under apartheid who were not free to choose schools, LER has a significant effect on learner achievement, par- ticularly in numeracy, while its effect is not significant among whites.
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Ethical challenges in assessment centres in South Africa

Ethical challenges in assessment centres in South Africa

without considering specific socio-political-historical and cultural factors that influence almost every facet of SA society. These authors explained that testing and assessment are essentially Western-world activities that were brought to Africa during the colonial era and therefore not naturally part of the African culture. Any efforts that might have been made to change or adapt assessments to suit local social conditions were not made until much later (Foxcroft, 1997; Foxcroft & Roodt, 2013). The development of assessments and testing almost inevitably reflected the racially segregated society it had evolved from (Foxcroft & Roodt, 2013). This may imply that assessments in the past were probably not always applied fairly and appropriately for all members of the SA society. It is against this background that it was agreed that all AC stakeholders have a responsibility to ensure that present-day ACs are fair and free from bias. This approach is aligned to international and national best practice guidelines that call for contextual adaptation in terms of social, political, institutional, linguistic and cultural differences (Assessment Centre Study Group Taskforce on Assessment Centres in South Africa, 2015; International Taskforce on Assessment Center Guidelines, 2015; International Test Commission, 2013).
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Modelling Asset Correlations of Revolving Loan Defaults in South Africa

Modelling Asset Correlations of Revolving Loan Defaults in South Africa

Chernih, Henrad & Vanduffel (2006) analysed corporate defaults and their impact on asset correlations. They used asset value data used from the Moody’s KMV Credit Monitor. They used a sample of companies’ asset returns for the period 1997 -2006. They divided the data into those using default data and those using asset data. They firstly estimate default correlations directly and then use assumptions regarding the joint asset value movements to back out the asset correlations. Secondly, they use the asset returns data to directly estimate asset correlations and convert them to asset correlations. Chernih, Henrad & Vanduffel (2006) results reveal that asset correlations are affected by the assumption that LGD’s are independent of the PD, and that the asset correlations estimated from default data must be increased in order to avoid underestimating the dependence between the PD and LGD. They deduce that default data is the best source of default correlations as there are no intermediate processes that need to be assumed in such a case. They however highlighted the challenges of acquiring such data, which makes such estimations difficult. The scarcity of such data is a result of the unwillingness of banks to avail their internal loss data. In this study, we employ retail default data from a South African b ank’s credit card portfolio to determine empirical asset correlations. Our results are compared to the BCBS’ prescribed asset correlations and results in previous literature. The empirical asset correlations are subsequently used to calculate a fair level of the South African bank’s economic capital.
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Validation of University of New Brunswick Ionospheric Modeling Technique with ionosonde TEC estimation over South Africa

Validation of University of New Brunswick Ionospheric Modeling Technique with ionosonde TEC estimation over South Africa

For more than a decade, ionospheric research over South Africa has been carried out using data from ionosondes geographically located at Madimbo (28.38°S, 30.88°E), Grahamstown (33.32°S, 26.50°E), and Louisvale (28.51°S, 21.24°E). The objective has been modelling the bottomside ionospheric characteristics using neural networks. The use of Global Navigation Satellite System (GNSS) data is described as a new technique to monitor the dynamics and variations of the ionosphere over South Africa, with possible future application in high frequency radio communication. For this task, the University of New Brunswick Ionospheric Modelling Technique (UNB-IMT) was applied to compute midday (10:00 UT) GNSS-derived total electron content (GTEC). GTEC values were computed using GNSS data for stations located near ionosondes for the years 2002 and 2005 near solar maximum and minimum, respectively. The GTEC was compared with the midday ionosonde-derived TEC (ITEC) measurements to validate the UNB-IMT results. It was found that the variation trends of GTEC and ITEC over all stations are in good agreement and show a pronounced seasonal variation for the period near solar maximum, with maximum values ( 80 TECU) around autumn and spring equinoxes, and minimum values ( 22 TECU) around winter and summer. Furthermore, the residual
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Development of a regional GPS-based ionospheric TEC model for South Africa

Development of a regional GPS-based ionospheric TEC model for South Africa

Fig. 2. A typical profile of electron density vs. height as obtained from ionosonde data. The specific profile pertains to 2005.01.31, 14:30 UT as recorded at the Grahamstown ionosonde. The bottom side profile (below the peak electron density value) is derived from a measured ionogram, while the topside profile is obtained by fitting a Chapman model to the peak electron density value. The total electron content (TEC) is obtained by integration of the density along the vertical height coordinate. For this profile the TEC was determined to be 19.6 TECU. Advances in space physics research, radio astronomy, radio communications, and precision navigation all depend on an accurate characterization of the ionosphere. These applications require higher spatial and temporal ionospheric information than is presently feasible with the existing ionosonde network. To supplement and improve the spatial resolution of existing ionospheric observations, measurements from GPS signals from the South African network of GPS receivers managed by the Chief Directorate Surveys and Mapping (CDSM) are being investigated.
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